Air supplying method for cluster hammer having nozzles installed

ABSTRACT

Disclosed is a method for supplying air to a cluster hammer in which a nozzle has been installed. An air distribution block  1  including an air distribution nozzle  3  formed therein is disposed under an air inlet cover  4  of the cluster hammer, into which air is introduced. The hammers  10  are disposed under the air distribution block  1  respectively. Compressed air which has passed through the air distribution nozzle  3  is supplied to each of the hammers  10,  and then the hammer  10  is operated. Even when the hammer  10  installed in the cluster hammer is in a flushing position, the cluster hammer is smoothly operated without creating the problems in the operation of the other hammers.

TECHNICAL FIELD

The present invention relates to an air supplying method of a drillingcluster hammer including two or more combined hammers, and moreparticularly to an air supplying method of the drilling hammer whichincludes a nozzle capable of uniformly supplying high-pressurecompressed air to each of the hammers.

BACKGROUND ART

In general, a hammer drilling the ground obtains a drilling force andcontrols the operation thereof by using air or fluid like water.

The structure of an ordinary hammer is disclosed as follows in KoreanRegistered Utility Model Publication No. 20-0429346. When compressed airsupplied from the air compressor reaches the air hammer through therotary head and the extension pipe, the piston within the air hammerhits the bit by performing an up and down repetitive action. Here, thebit breaks plurality of the ground, so that the drilling is made.

Here, the components of the used air hammer may include the chuck,sheath, piston, compressed air distributor, and top sub. The function ofeach of the components is as follows. The chuck is coupled under thesheath and couples the air hammer and the bit. The sheath surrounds theouter peripheral surface of the piston and causes the piston tonaturally perform a reciprocating action. The compresses air distributordistributes air to make the piston perform the reciprocating action. Thetop sub is coupled on the sheath and connects the sheath to theextension pipe for supplying the compressed air to the air hammer.

Also, in the air hammer disclosed in Korean Registered Utility ModelPublication No. 20-0273989, the drilling bit is installed in the hollowof the cylindrical housing constituting the body of the air hammer, thelower portion of the bit includes the fixed tooth including a pluralityof cemented carbide-material made balls and the magnified toothassembled outwardly. In a state where the housing of the air hammer isdisposed vertically at a drilling place, the bit installed in the hollowof the housing is driven. As a result, not only the fixed tooth andmagnified tooth provided in the lower portion of the head of the bitprotrude integrally toward the lower portion of the housing from theready state, but also the magnified tooth is enlarged outwardly due toits own weight. Here, the bit sprays the high pressure airsimultaneously with rotating, so that the soil or rock layer is drilled.

Meanwhile, in the cluster hammer including two or more combined hammers,the air or water fluid is introduced into the introduction path and isoptionally supplied to each of the hammers through the storage vesseland the internal structure.

Particularly, in the configuration of the cluster hammer including thetwo or more combined hammers, when the lower end of the hammer does notreach (that is, flushing) the rock or the ground, i.e., the drillingtarget due to the collapse of the lower ground of some of the multiplehammers, and then an empty space is generated between the lower end andthe drilling target, the compressed air which is supplied to the hammeris flown to the lower portion as it is. This causes the reduction of theamount of the compressed air which is supplied to the other hammers, andhas a bad influence on the powers of the other hammers.

DISCLOSURE Technical Problem

The embodiment of the present invention is designed to overcome theabove problems. In the embodiment of the present invention provides amethod for supplying air to the cluster hammer including nozzles forsmoothly operating the cluster hammer without creating the problems inthe operation of the other hammers, even when the hammer installed inthe cluster hammer is in the flushing position.

TECHNICAL SOLUTION

The embodiment of the present invention provides a method for supplyingair to the cluster hammer in which the nozzle has been installed. An airdistribution block 1 including an air distribution nozzle 3 formedtherein is disposed under an air inlet cover 4 of the cluster hammer,into which air is introduced. The hammers 10 are disposed under the airdistribution block 1 respectively. Compressed air which has passedthrough the air distribution nozzle 3 is supplied to each of the hammers10, and then the hammer 10 is operated. Even when the hammer 10installed in the cluster hammer is in a flushing position, the clusterhammer is smoothly operated without creating the problems in theoperation of the other hammers.

ADVANTAGEOUS EFFECTS

Therefore, the embodiment of the present invention has an effect that,even when the hammer installed in the cluster hammer is in the flushingposition, the cluster hammer is smoothly operated without creating theproblems in the operation of the other hammers.

DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of a device for supplying air to a clusterhammer in accordance with an embodiment of the present invention;

FIG. 2 is a view showing that the device for supplying air to thecluster hammer has been assembled in accordance with the embodiment ofthe present invention;

FIG. 3 is a cross sectional views of the device for supplying air to thecluster hammer in accordance with the embodiment of the presentinvention;

FIG. 4 is a cross sectional view of an air distribution nozzle of thedevice for supplying air to the cluster hammer in accordance with theembodiment of the present invention; and

FIG. 5 is a photograph showing an air operation experiment of the devicefor supplying air to the cluster hammer in accordance with theembodiment of the present invention.

<Description of reference numerals on main parts of the drawings>

1: air distribution block  2: air outlet 3: air distribution nozzle  4:air inlet cover 5 and 6: bolt 10: hammer

MODE FOR INVENTION

The embodiment of the present invention provides a method for supplyingair to a cluster hammer in which a nozzle has been installed. An airdistribution block 1 including an air distribution nozzle 3 formedtherein is disposed under an air inlet cover 4 of the cluster hammer,into which air is introduced. The hammers 10 are disposed under the airdistribution block 1 respectively. Compressed air which has passedthrough the air distribution nozzle 3 is supplied to each of the hammers10, and then the hammer 10 is operated. Even when the hammer 10installed in the cluster hammer is in a flushing position, the clusterhammer is smoothly operated without creating the problems in theoperation of the other hammers.

Also, water is used as a working fluid instead of the compressed air.

The embodiment of the present invention will be described in detail withreference to the accompanying drawings. FIG. 1 is a perspective view ofa device for supplying air to the cluster hammer in accordance with anembodiment of the present invention. FIG. 2 is a view showing that thedevice for supplying air to the cluster hammer has been assembled inaccordance with the embodiment of the present invention. FIG. 3 is across sectional views of the device for supplying air to the clusterhammer in accordance with the embodiment of the present invention. FIG.4 is a cross sectional view of the air distribution nozzle of the devicefor supplying air to the cluster hammer in accordance with theembodiment of the present invention. FIG. 5 is a photograph showing anair operation experiment of the device for supplying air to the clusterhammer in accordance with the embodiment of the present invention.

In the device for supplying air to the cluster hammer in accordance withthe embodiment of the present invention, the air distribution blockincluding a plurality of the air distribution nozzles (orifices) formedtherein is disposed under the air inlet cover into which air isintroduced. Also, a plurality of the hammers are disposed under the airdistribution block respectively. The compressed air which has passedthrough the air distribution nozzle is supplied to each of the hammers,and then the hammer is operated.

Describing the embodiment of the present invention in detail, airconsumption at a specific operating pressure of each of the hammers No.1, 2, 3, 4 . . . is determined in advance in the design of the hammer.

This is the unique characteristics of the hammer. For example, a 4-inchhammer consumes (requires) the compressed air of about 210 CFM at anoperating pressure of 200 psi (CFM stands for Cubic Feet per Minute).

Also, in the embodiment of the present invention, the position of ahammer bit is defined as follows.

The hammering position means that the bottom surface of the bit comes incontact with the rock (ground) and the hammer normally operates.

Flushing position means that the bottom surface of the bit does not comein contact with the rock, so that the bit is hung down from the hammer.At this time, this means that the compressed air supplied to the hammerdoes not operate the hammer and is flown to the outside of the hammer.

The embodiment of the present invention will be described. An airpressure generator of the embodiment of the present invention operatesone compressor with a capacity of 900 CFM/350 psi.

An operating method of the embodiment of the present invention includeseach of the hammers in which the nozzle has been installed. This may bedifferent from the conventional operating method without the nozzle.

First, the conventional operating method without the nozzle will bedescribed. For example, in a case where four hammers are operated, whenthe compressed air is ejected from one compressor with a capacity of 900CFM/350 psi and is supplied to the each hammer, the operating pressureof the hammer is 200 psi.

However, when three hammers normally operate and one hammer is in theflushing position, the operating pressures of the three normallyoperating hammers are reduced to 120 psi, so that a drilling efficiencyis remarkably reduced.

Meanwhile, unlike the conventional operating method, in the embodimentof the present invention, when the orifice-shaped air supply nozzle isinstalled in each of the hammers, the operating pressure of thecompressed air which is ejected from one compressor with a capacity of900 CFM/350 psi and is supplied to each of the hammers through thenozzle is 200 psi. Here, even when the three hammers normally operateand one hammer is in the flushing position, the operating pressures ofthe three hammers are maintained at 200 psi.

Also, in the embodiment of the present invention, the maximum amount ofair passing through the nozzle is determined based on the amount of airconsumption at a target operating pressure of the hammer, and thediameter Dn of the nozzle is determined based on the determined maximumamount of the air. The above-mentioned method for determining themaximum amount of the air passing through the nozzle on the basis of theamount of air consumption at the target operating pressure and fordetermining the diameter Dn of the nozzle on the basis of the determinedmaximum amount of the air is easily performed by using generated fluiddynamics equations. Therefore, a detailed description of the calculationwill be omitted.

Also, in the embodiment of the present invention, when the nozzle isinstalled as described above, the pressure loss of the nozzle itself isslight enough to be ignored.

Accordingly, according to the embodiment of the present invention, evenwhen the hammer installed in the cluster hammer is in the flushingposition, the cluster hammer is smoothly operated without creating theproblems in the operation of the other hammers.

What is claimed is:
 1. A method for supplying air to a cluster hammer inwhich two or more hammers (10) have been combined, wherein an airdistribution block (1) comprising an air distribution nozzle (3) formedtherein is disposed under an air inlet cover (4) of the cluster hammer,into which air is introduced, wherein the hammers (10) are disposedunder the air distribution block (1) respectively, wherein compressedair which has passed through the air distribution nozzle (3) is suppliedto each of the hammers (10), and then the hammer (10) is operated, andwherein even when the hammer (10) installed in the cluster hammer is ina flushing position, the cluster hammer is smoothly operated withoutcreating a problem in the operation of the other hammers.
 2. The methodof claim 1, wherein water is used as a working fluid instead of thecompressed air.